DESCRIPTION: UTI is one of the commonest infections i women, occurring in nearly 20% during their lifetime and costing nearly $1 billion annually. Research on the epidemiology and aetiology of UTI has concentrated on two groups of women: the young and healthy and the elderly and debilitated. In younger women, general debility, voiding problems, diabetes, and possibly, estrogen deficiency are risk factors. Little is known about risk factors for UTI in women soon after menopause, even though there are 56 million women aged 50 to 75. The main goal of this project is to prospectively determine the incidence of acute UTI and to assess risk factors for this problem in postmenopausal women, aged 50 to 75, living in the community. The primary aims will be to learn the relative effects of diabetes, postmenopausal estrogens, urine incontinence or increased post-void residual urine, and sexual activity on the risk of UTI. There are also plans to determine whether changes in the vaginal bacterial flora predispose to UTI in this age group and how risk factors, such as diabetes and estrogen therapy affect the vaginal flora. A prospective cohort study of community-dwelling, postmenopausal women is proposed. Participants will be 900 women randomly selected from the Group Health Cooperative of Puget Sound (GHC) enrollment database, along with 110 age-matched women, randomly selected from the GHC Diabetes Registry. Information about sexual activity,estrogen use, history of UTI, urinary continence and other exposures of interest will be obtained by interview. Urine and vaginal introital cultures along with measurement of the fasting serum glucose and the post-void residual urine volume will be performed at a clinic visit. Follow-up interviews and examinations will be performed annually for two years. Diabetic patients will be followed with glycosylated hemoglobin at least annually. Patients will monitor their urine monthly at home with leukocyte esterase/nitrite dipsticks and make a clinic visit if they test positive.